Sending Notifications Agent Skill

Sending real-time notifications

When to use this

You're adding notification support to a PostHog feature — for example, notifying a user when they're mentioned in a comment, when an alert fires, or when an approval is requested.

The facade API

All notification creation goes through a single function. Import from the facade, not from internal modules:

from products.notifications.backend.facade.api import (
    create_notification,
    NotificationData,
    NotificationType,
    Priority,
    TargetType,
)

Build a NotificationData and call create_notification:

event = create_notification(
    NotificationData(
        team_id=team.id,
        notification_type=NotificationType.ALERT_FIRING,
        priority=Priority.CRITICAL,
        title="Event ingestion latency > 30s",
        body="Events are queuing up. Ingestion pipeline is degraded.",
        target_type=TargetType.USER,
        target_id=str(user.id),
        resource_type="dashboard",
        resource_id="42",
        source_url="/dashboard/42",
    )
)

Returns a NotificationEvent on success, or None if the feature flag is disabled, no recipients were resolved, or the team doesn't exist. Safe to call in any context.

NotificationData fields

Required:

| Field | Type | Description |

| ------------------- | ------------------ | -------------------------------------------------------------------------- |

| team_id | int | Team context — used to look up the organization and check the feature flag |

| notification_type | NotificationType | Determines the icon in the UI |

| title | str | Notification headline (~100 chars recommended) |

| body | str | Longer description shown on expand. Can be empty string |

| target_type | TargetType | Who receives this: user, team, organization, or role |

| target_id | str | ID of the target (user ID, team ID, org UUID, or role UUID as string) |

Optional:

| Field | Type | Default | Description |

| --------------- | ---------------------------------- | -------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |

| resource_type | NotificationResourceType \| None | None | Access-controlled types (e.g. "dashboard") auto-filter recipients without viewer access |

| resource_id | str | "" | ID of the resource for linking |

| source_url | str | "" | Relative URL path (e.g. /dashboard/42), shown as link icon in UI |

| priority | Priority | NORMAL | normal = popover only; critical = popover + persistent toast |

| archivable | bool | False | Opt in to a per-recipient "archive" (dismiss) action that moves the notification to the recipient's Archived tab. When False, recipients can only mark it read/unread (the default pattern) |

| resolver | RecipientsResolver \| None | None | Custom recipient resolver. Default handles user/team/org/role targeting |

Choosing parameters

Notification type

| Type | When to use |

| -------------------- | ------------------------------------------------ |

| comment_mention | User was @mentioned in a comment or discussion |

| alert_firing | A monitoring alert threshold was breached |

| approval_requested | A change requires the user's approval |

| approval_resolved | An approval the user requested has been resolved |

| pipeline_failure | A data pipeline or batch export failed |

| issue_assigned | An error tracking issue was assigned to the user |

Priority

Be very careful with critical. It triggers a persistent toast popup that overlays the user's screen and must be manually dismissed. This is intentionally intrusive — reserve it for genuine emergencies like outages, security alerts, or SLA breaches. Overusing critical will train users to ignore notifications entirely. When in doubt, use normal.

Target type

| Target | target_id value | Recipients |

| -------------- | ----------------- | -------------------------------------- |

| user | User ID | Just that user |

| team | Team ID | All members of the team's organization |

| organization | Organization ID | All organization members |

| role | Role ID | All users with that RBAC role |

Resource type and access control

When resource_type matches an access-controlled resource (dashboard, feature_flag, experiment, etc.), recipients without viewer access are automatically excluded. For notification-only types (pipeline, approval, comment), no AC filtering is applied.

Delivery pipeline

Django (create_notification)
  → Postgres (NotificationEvent row)
  → Kafka (notification_events topic, on transaction commit)
  → Go livestream service (Kafka consumer)
  → Redis SPUBLISH (sharded pub/sub, keyed by org ID)
  → SSE (/notifications endpoint)
  → Browser (popover + optional toast)

Kafka publish happens on transaction.on_commit — won't fire if the transaction rolls back.

Adding a new notification type

• Add enum value in products/notifications/backend/facade/enums.py
• Add icon mapping in frontend/src/lib/components/NotificationsMenu/notificationToasts.tsx (NOTIFICATION_TYPE_ICONS) — the single icon source, read by getNotificationIcon, which only NotificationRow calls; the side panel gets the icon by rendering that row
• Add a label + description entry in frontend/src/lib/components/NotificationsMenu/NotificationRow.tsx (REALTIME_NOTIFICATION_TYPE_META) — drives the per-type notification preferences UI
• Run python manage.py makemigrations notifications

Testing

Mock the feature flag in tests:

from unittest.mock import patch

with patch("posthoganalytics.feature_enabled", side_effect=lambda flag, *a, **kw: flag == "real-time-notifications"):
    event = create_notification(data)